Comparison of the efficacy of percutaneous transforaminal endoscopic surgery combined with mini-incision oblique lumbar interbody fusion and anterolateral screw-rod fixation with minimally invasive surgery-transforaminal lumbar interbody fusion for single-segment lumbar spinal instability

English Keywords:Lumbar instability  Percutaneous transforaminal endoscopsurgery  Oblique lumbar interbody fusion  Transforaminal lumbar interbody fusion  Screw rod fixation

English Abstract:

  【Abstract】 Objectives: To evaluate the clinical efficacy and safety of percutaneous transforaminal endoscopic surgery(PTES) combined with mini-incision oblique lumbar interbody fusion(OLIF) and screw-rod fixation under local anesthesia for the treatment of single-segment lumbar instability, and to compare it with minimally invasive surgery-transforaminal lumbar interbody fusion(MIS-TLIF). Methods: A total of 68 patients with single-segment lumbar instability and neurological symptoms who were treated in the Department of Orthopedics at Zhongshan Hospital, Fudan University, between June 2017 and April 2019 were retrospectively analyzed. Of the patients, 33 underwent PTES combined with mini-incision OLIF and screw-rod fixation(PTES+OLIF, Group A, 20 males and 13 females; age 59.4±8.0 years; L3/4 4 cases, L4/5 29 cases), while the other 35 underwent MIS-TLIF(Group B, 22 males and 13 females; age 61.2±7.5 years; L3/4 4 cases, L4/5 31 cases). There were no significant differences between the two groups in terms of age, sex ratio, or level of involvement. The operative time, blood loss, incision length, fluoroscopy times, and length of hospital stay were compared between the two groups. Visual analog scale(VAS) scores for back pain and leg pain were recorded and compared at preoperation, immediate postoperation, 1 month, 2 months, 3 months, 6 months, 1 year, and 2 year time points. The Oswestry disability index(ODI), intervertebral space height(ISH), lumbar lordosis(LL), surgical segment lordosis angle(SLA), intraoperative and postoperative complications, and fusion grade according to the Bridwell classification were also compared and evaluated at preoperation, immediate postoperation, and postoperative 2 years. Results: Both groups of patients successfully completed the surgeries without intraoperative complications. The operative time was 49.5±7.6min for PTES under local anesthesia, and 75.3±13.1min for OLIF under general anesthesia in group A, while it was 103.9±17.6min for MIS-TLIF under general anesthesia in group B. The intraoperative blood loss was 30mL(range 15-110mL) in group A and 80mL(range 50-310mL) in group B. The incision length was 8.0±1.2mm for PTES, and 39.0±3.3mm for OLIF in group A; The incision length was 41.5±2.8mm for MIS-TLIF in group B. The number of fluoroscopy was 6(range 5-8) for PTES and 7(range 5-10) for OLIF in group A, and 7(range 6-11) in group B. The length of hospital stay was 4d(range 3-5d) in group A and 7d(range 6-10d) in group B. Both groups were followed up for 2 years. Compared with preoperative levels, the VAS scores for back and leg pain, and ODI were significantly decreased at all postoperative time points(P<0.05) in both groups. The immediate postoperative VAS score for back pain in group A was significantly lower than that in group B(P<0.000). However, at subsequent time points, no significant differences in VAS scores for back and leg pain, or ODI were found between the two groups(P>0.05). The ISH and SLA at immediate postoperation in group A were significantly higher than those in group B(P=0.018, P=0.002). At 2 years′ follow-up, the ISH in group A remained significantly higher than that in group B(P=0.004). There was no significant difference in LL between the two groups at all postoperative time points(P>0.05). 25 cases(75.8%) in group A achieved grade Ⅰ fusion, and 8 cases(24.2%) achieved grade Ⅱ fusion; In group B, 21 cases(60.0%) achieved grade Ⅰ fusion, and 14 cases(40.0%) achieved grade Ⅱ fusion. There was no significant difference in the fusion grade between the two groups(P=0.126). One patient in group A developed hip flexion pain and weakness, which resolved at 3d after operation. Two cases of dural tear with cerebrospinal fluid leakage occurred in group B, without neurological symptoms, and resolved after drainage tube removal at 7d postoperatively. No incision infections, permanent nerve damage, major vascular injury, implant loosening, or subsidence were observed. The postoperative complication rate was not significantly different between the two groups(2.8% vs 5.7%, P=0.590). Conclusions: Compared with MIS-TLIF for the treatment of single-segment lumbar instability, PTES combined with mini-incision OLIF and screw-rod fixation offers smaller trauma, less blood loss, shorter general anesthesia duration, faster relief of back pain, and better recovery of ISH and SLA. PTES combined with mini-incision OLIF and screw-rod fixation is an excellent choice for treating patients with lumbar instability who need direct decompression.